Encoding systems such as MPEG-2 (Moving Picture Experts Group 2) video, H.264, and the like have been adopted in digital broadcasting. Since picture encoding is carried out by use of picture-to-picture prediction in these systems, decoding of the encoded video data cannot start from a picture in an arbitrary position; decoding can only start from pictures in particular positions. A picture at which decoding can start will be referred to as a key picture below. Specific examples of key pictures include I-pictures (Intra pictures) in MPEG-2 video and IDR pictures (Instantaneous Decoder Refresh pictures) in H.264. A problem with digital broadcasting is that since video data cannot be decoded during the interval from the execution of a service selection operation performed by the user to the acquisition of a key picture, there is necessarily a long elapse of time from execution of the service selection operation until the start of video picture display.
A technique for shortening the time needed from execution of the service selection operation to the start of video picture display is disclosed in, for example, patent reference 1. The receiver described in patent reference 1 has a first receiver that receives compressed video data corresponding to a selected channel, a second receiver that receives self-contained and compressed still image data, a storage unit that stores a plurality of self-contained and compressed still image data that have been received by the second receiver, an acquisition unit that, after a switch to a new channel, acquires self-contained and compressed still image data corresponding to the channel from the storage unit, and a display controller that decodes the self-contained and compressed still image data acquired by the acquisition unit and displays the decoded image on a display device until the compressed video data corresponding to the channel received by the first receiver after the channel switch can be decoded and displayed on the display device.